AGR – 1 Long-term Neuropsychological Follow-up after 7 Years of Responsive Neurostimulation (RNS)

Abstract Objective The current case is a 35-year-old woman with a history of bitemporal lobe epilepsy who has had responsive neurostimulation (RNS) for 7 years and 3 months. The original RNS System Pivotal trial assess neurocognitive outcomes after 2 years (Loring et al., 2015). A more recent study found that self-reported cognitive functioning on the Quality of Life in Epilepsy-89 was improved after 9 years (Nair et al., 2020). The current case adds to the literature by providing objective data for a patient with RNS for over 7 years. Method The patient had onset of seizures at age 26 in 2014. Her ongoing epilepsy care has included video EEGs, intracranial monitoring, MRI, PET, two Wadas, and three neuropsychological evaluations (2015, 2021, and 2024). Multiple diagnostic studies confirmed bitemporal epilepsy. She underwent RNS implantation in bilateral mesial temporal lobes in 2016. Results The patient’s pre-RNS neuropsychological findings in 2015 included average verbal and visual memory and below average-to-low average language functioning (confrontation naming, letter fluency, verbal abstract reasoning). Her first post-RNS neuropsychological findings in 2021 included average visual memory, below average-to-low average verbal memory, and exceptionally low-to-below average language. The patient noted significant anxiety during her 2021 evaluation. Her second post-RNS neuropsychological findings in 2024 was entirely normal, showing resolution of prior deficits in verbal memory and language. Conclusions This case presents objective neuropsychological data for RNS over a longer follow-up interval than was investigated in the original trial. In this patient, there were no persistent cognitive declines associated with RNS for over 7 years.